G.2.3.1 Difference value %[format]? special texts

The use of the other difference values as listed here is to calculate
distance values between two dates. In case these special texts are
directly lead by a ‘-’ character, e.g. ‘-%d’, Gcal switches
the sign of the computed value.

You may depreciate the special meaning of the ‘-’ character
—in case this character itself is needed— by placing a ‘\’
(backslash) character before it, e.g. ‘\-’. If you need the
‘\-’ characters themselves, you have to protect the ‘\’
(backslash) character by another ‘\’ (backslash) character,
e.g. ‘\\-’.

The following other difference values %[format]?
special texts are respected:

%d

Specifies the current respectively queried day
relative to the actual system date (≡today), e.g.:

The resource file line ‘0 %d days gone’
will be expanded to
→ ‘-10 days gone’,
in case you call Gcal with the -c10- option and no command.

%w

Specifies the current respectively queried week relative to
the actual system date (≡today). Started weeks are counted
as complete weeks.

%m

Specifies the current respectively queried month relative to
the actual system date (≡today). Started months are counted
as complete months.

%y

Specifies the current respectively queried year relative to
the actual system date (≡today). Started years are counted
as complete years. This special text must always be trailed by
a whitespace character which is removed in output!

An example:

Supposing, the actual system date is the 4th September 1999. To calculate,
how many days, weeks, months and years are between the actual system date
and the birthday of a person, who is born on 21st September 1962, Gcal can
be called as follows:

Please do not confound the relative year number %[format]y
special text with the age value %B special text
(see Age value %[format]B[date] special text).
The %y special text counts started years as complete years,
while the %B special text does not.